German submarine U-2357 was a Type XXIII U-boat of Nazi Germany's Kriegsmarine during World War II. She was ordered on 20 September 1944, and was laid down on 21 October 1944 at Deutsche Werft AG, Hamburg, as yard number 511. She was launched on 20 December 1944 and commissioned under the command of Oberleutnant zur See Erwin Heinrich on 13 January 1945.